I suggest you ...

Smaller pinned chat window

It would be cool if we could resize the pinned chat-window while playing. So change the number of lines LOWER!
I think now its too height and that can disturb players especially in 1024x768 or lower pixel number.
It would be very useful for 2vs2 or 3vs3 games

The chat window’s height is limited by the height of the player list. Making it shorter would mean either drawing only a part of the player list, or hiding the list completely.

Would you be interested in a compromise – adding a registry tweak to use a smaller font for the chat? W:A already uses a smaller font for resolutions lower than 1024×768. This reduces the pinned chat panel height from 116 pixels to 88.